Hacker News new | past | comments | ask | show | jobs | submit login

Great reply. The wiki also has a long discussion about Helium 3. http://en.wikipedia.org/wiki/Helium-3 Fusion produces neutrons either in the first or secondary reactions, but there are ways to minimize the amount of them and their energy (and damage/radioactivity)to where you don't generate "nuclear waste". There is an interesting continuum of fusion reactions from pure D-D (which produces little energy, but lots of lower energy neutrons) to D-He3 (that produces some neutrons and lots of energy) to pure He3-He3 (that is called 'anuetronic').

D-D fusion makes Tritium (that decays into He3), Helium 3, or Helium 4 through the fusion process itself, with no breeding.

We believe that there is a correct ratio called Self-Supplied in which you have a small amount of 2.4 MeV neutrons, only deuterium as an input fuel, and the majority of the energy is from the Helium 3 fusion. The hard part is how to separate out the right isotope mixture from the exhaust between pulses.




He3 is never added? How long can a reactor run without supplying He3?

(This thread is having a hard time settling on a single isotope notation.)


The best way to make Helium 3 is with Deuterium fusion. Its a very interesting bootstrap question -- how do you build new reactors, if you have to have working reactors to generate fuel?


So really it's a mixed-mode D-D/3He-D reactor? How much more common are D-D reactions than 3He-D reactions while the reactor is running normally?

How much does the initial charge of 3He cost, given that the stuff costs $7,000 a gram?




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: